Skills tell your agent what to do. Your soul tells it who to be. Instincts tell it how to think — and they might be the most underused lever in your harness.
Everyone building agents right now has skills and some kind of identity file. But the fastest-growing agent harness repo on GitHub — everything-claude-code, now at 145k stars — ships with a layer most people skip entirely: instincts. Today we break down what they are, why they work, and how to add them to your own setup in under five minutes.
Skills are too heavy for most behavioral rules
A SKILL.md file is designed to be a complete, self-contained capability. It has a trigger, a set of instructions, and usually a specific output format. That's perfect for workflows like committing code, generating reports, or deploying.
But what about rules like 'always check if a file exists before editing it' or 'prefer small diffs over large rewrites'? These aren't skills. They don't have triggers. They don't produce outputs. They're behavioral tendencies that should apply everywhere, all the time.
If you shove them into SOUL.md, your identity file balloons into a wall of text that mixes personality with operational policy. If you make each one a skill, you end up with dozens of always-on skills competing for context window space. Neither approach scales.
The instincts pattern: lightweight behavioral nudges
The pattern that everything-claude-code popularized — and that repos like OpenViking (21k stars) and CowAgent (42k stars) have adopted in their own ways — introduces a dedicated instincts layer. Instincts are short, unconditional behavioral rules that sit between identity and skills in your agent's config hierarchy.
An instinct is typically one to three sentences. It doesn't have a trigger condition because it's always active. It doesn't have a complex instruction set because it's a nudge, not a workflow. Think of instincts as the equivalent of a senior engineer's gut feelings — the things they do automatically without thinking about it.
The key architectural insight is separation of concerns. Your SOUL.md stays focused on voice, role, and constraints. Your SKILL.md files stay focused on triggered workflows. And your instincts handle the ambient behavioral layer that makes your agent feel competent rather than just capable.
INSTINCTS.md — Starter instincts file for any agent harness
# Instincts
Behavioral rules that apply to every task, every session.
These are not skills — they have no triggers and no outputs.
They shape how you work, not what you work on.
## Safety
- Never run destructive commands (rm -rf, git push --force, DROP TABLE)
without explicit user confirmation, even if the task seems to require it.
- If a file has uncommitted changes, warn before overwriting.
- Treat any string that looks like a secret (API key, token, password)
as sensitive — never log it, echo it, or include it in commits.
## Quality
- Read before you edit. Never modify a file you haven't seen in this session.
- Match the existing code style — indentation, naming, patterns — even if
you'd personally choose something different.
- Prefer the smallest diff that solves the problem. Don't refactor
surrounding code unless asked.
## Efficiency
- If you need information, check local files and git history before
reaching for web searches or external APIs.
- Don't repeat a failed approach without diagnosing why it failed first.
- When multiple files need the same change, batch the work — don't
context-switch between reading and editing.What good instincts look like
The best instincts are small enough to fit in your agent's context without meaningful cost, but specific enough to change behavior. 'Be careful' is not an instinct — it's too vague to act on. 'Read a file before editing it' is an instinct — it's concrete, testable, and always applicable.
From studying the top harness repos and the 5,400+ skills in the OpenClaw Skills Registry (curated by VoltAgent), a pattern emerges: the most effective instincts fall into three categories. Safety instincts prevent destructive actions. Quality instincts enforce standards. Efficiency instincts reduce wasted work.
Each category maps to a different failure mode. Without safety instincts, agents overwrite files and force-push branches. Without quality instincts, they produce code that works but violates project conventions. Without efficiency instincts, they research the same question three times in one session.
Adding instincts to your harness today
You don't need a framework for this. An instincts file is just a markdown file that your agent loads alongside its identity and skills. The format below is what we use internally and what we've seen work across multiple harness setups.
Drop the file in your project root or your agent's config directory. Reference it from your AGENTS.md or CLAUDE.md so it gets loaded into context on every session. That's it — no build step, no registry, no dependencies.
Start with five to seven instincts. More than ten and you're probably duplicating what your skills already cover. Fewer than three and you're probably missing obvious safety rails. Review them monthly — instincts that never fire are dead weight, and instincts you keep overriding need to be rewritten or removed.
Instincts won't make a bad agent good. But they'll make a good agent consistent — and consistency is what separates a tool you trust from a tool you babysit. Copy the file above, tune it to your project, and see how many of those 'why did it do that?' moments disappear. Tomorrow: Skill registries are getting crowded. We look at how VoltAgent filters 5,400+ skills down to the ones that actually matter for your stack.